Plastic floorings using concave portions and convex portions

ABSTRACT

Disclosed is a new plastic flooring that is assembled by concave portions and convex portions. The plastic flooring provides space between the concave portions and convex portions. The space absorbs the heat expansion of the plastic flooring such that the deformation of the plastic flooring is prevented. Also, the space stores an adhesive on a bottom floor such that crevices between the plastic flooring are prevented.

BACKGROUND OF THE INVENTION

[0001] (a) Field of the Invention

[0002] The present invention relates to plastic floorings using concaveportions and convex portions, specifically to an assembly structure ofthe plastic floorings absorbing heat expansions as well as forming aspace area between the concave portions and the convex portions tominimize the deformation of the plastic floorings so that aliensubstances of a floor surface does not protrude up to the surface of thefloorings.

[0003] (b) Related Arts

[0004] Plastic floorings used for installing floors of a building areindividually manufactured so that they have a surface area of a certainstandard. The plastic floorings are used with other types of plasticfloorings to constitute the floors of the building. Typical plasticfloorings mostly have a form of a square shape having perpendicularcorners and a certain thickness. At the side surfaces of each flooring,unique assembly structures are implemented which allow them to beassemble with other types of floorings.

[0005]FIG. 8 is a cross section view of plastic floorings according to aprior art in which each plastic floorings (1) has steps in a form ofstairs connected to other plastic floorings (1′) so that multiplefloorings (1, 1′) are assembled in a continuous overlapping manner.

[0006] Above assembly structures, however, have the shortcomings ofhaving a height difference between the floorings when the floor to whichthe floorings are installed is bumpy because the floorings do notclosely and firmly adjoin each other in the area connecting thefloorings.

[0007] Therefore, plastic floorings (3) having concave portions (5) andconvex portions (7) on the side surfaces of each flooring (3) asillustrated in FIG. 9 have been proposed to closely adjoin theconnecting areas of the floorings.

[0008] That is, the plastic flooring (3) has the convex portion (7) atthe left side of the drawing and concave portion (5) at the right sideof the drawing. The assembly of the floorings (3, 3′) is enabled byinserting the convex portion (7) into the concave portion (5) of theother plastic floorings (3′) and engaging the concave portion (5) withthe convex portion (7) of the other plastic floorings (3′).

[0009] In floorings (3) with such a structure, however, the concaveportions (5) and the convex portions (7) engage in a close manner sothat when the heat from the bottom surface is transferred to the plasticflooring, each plastic flooring expands toward the other plasticflooring adjacent to it. As a result, distortion in the connectionportion of the flooring (3) occurs as can seen in FIG. 10, whichseriously degrades the quality of the floorings.

[0010] Furthermore, many alien substances such as adhesives exist on thebottom floor (9) to which the floorings (3) are installed. After theinstallation, the alien substances (3) protrude beyond the connectionportions, exposing itself out on the surface of the floorings. Thesealien substances weaken the adjoining force between the concave portion(5) and the convex portion (7), which causes the problem ofdeteriorating adjoining force among the floorings.

SUMMARY OF THE INVENTION

[0011] An object of the present invention is to provide an assemblystructure of plastic floorings using concave portions and convexportions which absorb the heat expansion of the floorings as well aspreventing alien substances of bottom surface from protruding onto theflooring surface so as to minimize the distortion of the plasticfloorings.

[0012] In order to achieve this object, the present invention comprises;a first flooring having a first side surface with a concave portion anda second side surface with a convex portion, and a second flooringassembled to the side surface of the first flooring through anengagement of the convex portions and the concave portions, said concaveportion and the convex portions\ forming abutting surfaces engaging eachother in a close manner and at least one facing surface disposed so thatthey face each other and have gaps in between, providing a heatexpansion tolerance portion between the concave portion and the convexportion.

BRIEF DESCRIPTION OF THE DRAWING

[0013]FIG. 1 is a cross section view of a plastic flooring according tothe present invention.

[0014]FIG. 2 is a detailed view of the plastic flooring according to thepresent invention in an assembled state.

[0015]FIG. 3 is a cross section view of the plastic flooring accordingto another embodiment.

[0016] FIGS. 4 to 6 are schematic drawings explaining the manner ofassembling the plastic flooring according to the present invention.

[0017]FIG. 7 is a cross section view of the plastic flooring accordingto another embodiment of the present invention.

[0018]FIG. 8 is a cross section view of the plastic flooring accordingto a prior art.

[0019]FIG. 9 is a cross section view of the plastic flooring accordingto another prior art.

[0020]FIG. 10 is a schematic drawing explaining the distortionphenomenon of the plastic floorings.

DETAILED DESCRIPTION AND THE PREFERRED EMBODIMENTS

[0021] Hereinafter, preferred embodiments of the present invention willbe explained in detail with reference to the drawings.

[0022]FIG. 1 is a cross section view of the plastic flooring accordingto the present invention. FIG. 2 is a drawing depicting the assembledplastic flooring of FIG. 1.

[0023] As illustrated in FIGS. 1 and 2, the plastic flooring comprisesfirst flooring (6) having a first side surface (4) with a concaveportion (2) and a second side surface (10) having a convex portion (8).Second flooring (12) is assembled with the first flooring (6) through anengagement of the concave portion (2) and the convex portion (8).

[0024] The concave portion (2) and the convex portion (8) form abuttingsurfaces (14 a, 14 b) closely engaging each other so that the firstflooring (6) and the second flooring (12) are firmly assembled. Also, apair of facing surfaces (16 a, 16 b, 18 a and 18 b), disposed with gapsin between, are formed so that a heat expansion tolerance portion S isprovided between the concave portion (2) and the convex portion (8).

[0025] First, the first flooring (6) and the second flooring (12) haveflat upper surfaces. The closely abutting surfaces (14 a, 14 b) formedon the concave portion (2) and the convex portion (8) are disposed sothat they are parallel to the upper surface of the first flooring (6)and the second flooring (12). More specifically, the closely abuttingsurface (14 a) of the concave portion (2) is defined as a surfacestarting from point A of the drawing, extending to point B. The closelyabutting surface (14 b) of the convex portion 8 is defined as a surfacestarting from point A′ of the drawing, extending to point B′.

[0026] Here, the height of the closely abutting surface (14 b) of theconvex portion (8) with respect to the lower surface of the firstflooring (6) and the second flooring (12) is in fact higher than theheight of the closely abutting surface (14 a) of the concave portion (2)with respect to the lower surface of the first flooring (5) and thesecond flooring (12) so that the closely abutting surface (14 b) of theconvex portion (8) comes into contact on the closely abutting surface(14 a) of the concave portion (4) when the first flooring (6) and thesecond flooring (12) are assembled.

[0027] Consequently, the connecting portions of the first flooring (6)and the second flooring (12) abut closely and firmly through the closelyabutting surfaces (14 a, 14 b) provided at the concave portion (2) andthe convex portion (8). Thus, even when the floor surface (not shown) isbumpy, the height difference between the first flooring (6) and thesecond flooring (12) due to the bumps are suppressed.

[0028] Also, the facing surfaces formed at the concave portion (2) andthe convex portion (8) consist of the slanted surfaces (16 a, 16 b)maintaining a certain angle with the upper surface of the first flooring(6) and the second flooring (12) and perpendicular surfaces (18 a, 18 b)connecting the slanted surfaces (16 a, 16 b) with each closely abuttingsurface (14 a, 14 b). The slanted surface (16 a) and the perpendicularsurface (18 a) formed at the concave portion (2) maintain a certain gapwith the slanted surface (16 b) and the perpendicular surface (18 b)formed on the convex portion (8), thereby providing space between theconcave portion (2) and the convex portion (8).

[0029] More specifically, the slanted surface (16 a) of the concaveportion (2) is defined as a surface starting from point C of thedrawing, extending to point D of the drawing. The slanted surface (16 b)of the convex portion (8) is defined as a surface starting from point C′of the drawing, extending to point D′ of the drawing. Also, theperpendicular surface (18 a) of the concave portion (2) is defined as asurface starting from point D of the drawing, extending to point A ofthe drawing. The perpendicular surface (18 b) of the convex portion (8)is defined as a surface starting from point D′ of the drawing, extendingto point A′ of the drawing.

[0030] Particularly, the perpendicular surfaces (18 a, 18 b) of theconcave portion (2) and the convex portion (8) face each other with agap of d1 in between. The slanted surfaces (16 a, 16 b) of the concaveportion (2) and the convex portion (8) maintain angles of a and p withrespect to a virtual normal perpendicular to the upper surface of thefirst flooring (6) and the second flooring (12). α and β are configuredso that the following conditions are met.

[0031] [Mathematical formula]

α=65˜75°, β=65˜75°, α≧β

[0032] Above conditions are necessary to facilitate the engagementbetween the concave portion (2) and the convex portion (8). If α issmaller than β, the insertion of the convex portion (8) into the concaveportion (2) is not smooth, which causes such problems as fracture in theconvex portion (8) during the assembly of the first flooring (6) and thesecond flooring (12).

[0033] In this manner, the structure of the concave portion (2) and theconvex portion (8) forms a space, that is, a heat expansion toleranceportion (S), between the concave portion (2) and the convex portion (8).The heat expansion tolerance portion (S) absorbs the heat expansion ofthe first flooring (6) and the second flooring (12) when the firstflooring (6) and the second flooring (12) heat expands from the heat ofthe bottom surface, allowing the assembled floorings to maintain a flatshape, consequently, preventing the deformation of the floorings.

[0034] Furthermore, the heat expansion tolerance portion (S) traps thealien substances such as adhesives on the floor surface within itsinterior, effectively preventing the phenomena of the alien substancesprotruding on to the surface of the first flooring (6) and the secondflooring (12) as well as formation of crevice of the first and secondfloorings (6, 12) by the alien substances.

[0035] On the other hand, the first flooring 6 and the second flooring(12) forms an additional heat expansion tolerance portion (S′) betweenthe first side surface (4) with the concave portion (2) and the secondside surface (10) with convex portion (8) as well as the heat expansiontolerance portion (S) formed by the concave portion (2) and the convexportion (8) of the first and the second floorings (6, 12). Theadditional heat expansion tolerance portion (S′) supplements thefunction of absorbing the heat expansion of the flooring and preventionof the crevices.

[0036] For such purposes, the first side surface (4) provides asupplemental slanted surface (20 a) starting from the upper surface ofthe first flooring (6) extending toward the interior of the firstflooring (6) and connected to the slanted surface (16 a) of the concaveportion (2). The second side surface (10) provides a supplementalslanted surface (20 b) starting from the upper surface of the secondflooring (12) extending toward the interior of the second flooring (12)and connected to the slanted surface (16 b) of the convex portion (8).Thus, additional space, that is the heat expansion tolerance portion(S′), is formed between the supplemental slanted surfaces (20 a, 20 b).

[0037] More specifically, the supplemental slanted surface (20 a) of thefirst side surface (4) is configured as a surface having an angle of χwith respect to a virtual normal, starting from point E and extending topoint C of the drawing. The supplemental slanted surface (20 b) of thesecond side surface (10) is configured as a surface having an angle of δwith respect to a virtual normal, starting from point E and extending toC′ of the drawing.

[0038] Preferable, χ and δ satisfy the following conditions.

[0039] [Mathematical Formula 2]

χ=0˜8°, δ=0˜8°, χ≧δ, χ+δ=0˜16°

[0040] These conditions are for absorbing the heat expansion of thefloorings by forming sufficient heat expansion tolerance portion (S′)between the first side surface (4) and the second side surface (10)while enabling the holding of the aliens substances therein. If χ+δ isset below 0°, then the heat expansion tolerance portion cannot performits function whereas if the χ+δ is set above 16°, then the strength ofthe first and the second floorings (6, 12) decreases because of theexcessive heat expansion tolerance portion so that problems such asfracturing at the corners occur when the floorings are subject topressure.

[0041] Furthermore, the first side surface (4) provides a perpendicularsurface (22 a) connected to the closely abutting surface (14 a) of theconcave portion (2) at the lower surface of the first flooring (6). Thesecond side surface (10) provides a perpendicular surface (22 b)connected to the closely abutting surface (14 b) of the convex portion(8) at the lower surface of the second flooring (12). The perpendicularsurfaces (22 a, 22 b) of the first and the second side surfaces (4, 10)maintain a gap of d2 between each other, forming a heat expansiontolerance portion (S″).

[0042] The heat expansion tolerance portion (S″) defined by the gap d2contacts the floor surface directly. Therefore, it absorbs the heatexpansion which occurs when the lower surfaces of the first and thesecond floorings (6, 12) expand because of the heat from the bottomfloor as well as directly holding alien substances existing on thebottom floor so that the alien substances do not protrude beyond theclosely abutting surface (14 a) and (14 b) of the concave portion (2)and the convex portion (8).

[0043] Therefore, it is preferable to configure the heat expansiontolerance portion (S″) as identical to above d1 or satisfy the followingconditions considering the heat applied to the floorings and thecondition of the flooring surfaces to which the floorings are beinginstalled.

[0044] [Mathematical Formula 3]

d2=2×d1

[0045] In these plastic floorings according to the present embodiment,the connecting portions of the first and the second floorings (6, 12)are firmly and closely abutted by the engagement of the closely abuttingsurfaces (14 a, 14 b) of the concave portion (2) and the convex portion(8) while the heat expansion tolerance portions (S, S′ and S″) absorbthe heat expansion of the floorings and holds the alien substances ofthe floor surface, providing the merit of preventing the deformation ofthe floorings caused by the heat expansion and the alien substances.

[0046] Here, when the thickness of the floorings is assumed to be 1,preferable configurations are as follows: the thickness from the uppersurface of the first and the second floorings (6, 12) to the slantedsurface (14 a, 14 b) of the concave portion (2) and the convex portion(8) is ¼, the thickness of the slanted surface (16 a, 16 b) of theconcave portion (2) and the convex portion (8) is ¼, the thickness ofthe perpendicular surface (18 a, 18 b) of the concave portion (2) andthe convex portion (8) is ¼, and the thickness from the closely abuttingsurface (14 a, 14 b) of the concave portion (2) and the convex portion(8) to the lower surface of the first and the second floorings (6) and(12) is ¼.

[0047] On the other hand, the plastic floorings according to the presentinvention can be assembled in the following manner using the engagementstructure of the concave portion (2) and the convex portion (8).

[0048] First, as shown in FIG. 4, the concave portions (2) are formed atthe two adjacent side surfaces and the convex portions (8) are formed onthe remaining two other side surfaces of each plastic flooring. Theconvex portion (8) of the second flooring (24) is assembled by fittingit into the concave portion (2) of the first flooring (22). The convexportion (8) of the third flooring (26) is assembled by fitting it intothe concave portion (2) of the first and the second floorings (22, 24).

[0049] As another embodiment, a first group of plastic flooring (28 a,28 b) has the structure having the concave portions at three adjacentside surfaces and having convex portion (8) at remaining one sidesurface as shown in FIG. 5. A second group of plastic floorings (30) hasthe structure of having the convex portions (8) at three adjacent sidesurfaces and the concave portion (2) at one remaining side surface.

[0050] To the concave portions (2) of the first flooring (28 a)belonging to the first group, the convex portions (8) of the secondfloorings (28 b) are assembled in one direction. To the side surface ofthe plastic floorings (28 a, 28 b) belonging to the first group, theplastic floorings (30) of the second group are connected and assembled.

[0051] In still another embodiment as shown in FIG. 6, the plasticflooring (32) of the first group has the concave portions (2) formed atall four side surfaces whereas the plastic flooring (34) of the secondgroup has the convex portions (8) formed on all four side surfaces. Atall four side surfaces of the plastic flooring (32) belonging to thefirst group, the plastic floorings (34) of the second group areconnected and assembled.

[0052] The plastic flooring assembled in these manners can be formedwholly of plastic while it can also comprise a substrate layer (36) anda surface layer (38) located above the upper surface of the substratelayer (36) attributing pattern to the floorings, and a balance layer(40) which prevents the contraction and expansion of the flooring andmaintaining the flatness as shown in FIG. 7.

[0053] For example, the surface layer (38) can be of natural material ofa patterned wood layer and the balance layer (40) is a glass fiberimpregnated with plastic. The plastic floorings can establish thedimension stability by the balance layer (40).

[0054] Preferably, the corners of the surface layer (38) and the balancelayer (40) are beveled so that the beveled portion along with the heatexpansion tolerance portion (S) absorb the heat expansion of the plasticflooring caused by the heat from the bottom surface; thus, preventingthe occurrence of the height difference between the floorings.

[0055] According to the present invention, the formation of the heatexpansion tolerance portion (S) between the concave portion (2) and theconvex portion (8) has the effect of minimizing the deformation of theplastic floorings by absorbing the heat expansion of the floorings andpreventing the alien substances of the bottom floor from protruding upto the surface of the floorings.

What is claimed is:
 1. A plastic flooring comprising, a first flooringhaving a first side surface with a concave portion; and a secondflooring having a second side surface with a convex portion, said secondflooring assembled to the side surface of the first flooring byinserting the convex portion into the concave portion, said concaveportion and the convex portions providing abutting surfaces engagingeach other in a close manner; and at least one facing surface disposedfacing each other with gaps in between so that a heat expansiontolerance portion is provided between the concave portion and the convexportion.
 2. The plastic flooring of claim 1, wherein the first flooringand the second flooring comprise a flat upper surface and the abuttingsurface of the concave portion and the convex portion being a horizontalsurface parallel to the upper surfaces of the first flooring and thesecond flooring.
 3. The plastic flooring of claim 2, wherein the firstflooring and the second flooring comprise a lower surface, the height ofthe abutting surface of the convex portion with respect to surface beingbigger than the height of the abutting surface of the concave portionwith respect to the lower surface so that the abutting surface of theconvex portion abuts the abutting surface of the concave portion on theabutting surface of the concave portion.
 4. The plastic flooring ofclaim 1, wherein, the facing surfaces of the concave portion and theconvex portion comprise, slanted surfaces maintaining a certain anglewith respect to the upper surface of the first and the second flooring,and perpendicular surfaces connecting the slanted surfaces and theabutting surfaces, said slanted surface and the perpendicular surfacedisposed in a manner facing each other with a gap in between.
 5. Theplastic flooring of claim 4, wherein the concave portion and the slantedsurface maintain an angle of a with respect to a normal perpendicular tothe upper surface of the first flooring, and the slanted surface of theconvex portion maintaining an angle of β with respect to the normal,wherein α and β satisfy the following conditions: α=65˜75°, β=65˜75°,α≧β.
 6. The plastic flooring of claim 4, wherein the first and thesecond floorings form an additional heat expansion tolerance portionbetween the first side surface and the second side surface.
 7. Theplastic flooring of claim 6, wherein the first side surface provides asupplemental slanted surface starting from the upper surface of thefirst flooring toward interior of the first flooring and connected tothe slanted surface of the concave portion, and the second side surfaceprovides a supplemental slanted surface starting from the upper surfaceof the second flooring toward the interior of the second flooringconnected to the slanted surface of the convex portion so that a heatexpansion tolerance portion is provided between the supplemental slantedsurfaces of the first and the second side surfaces.
 8. The plasticflooring of claim 7 wherein, the supplemental slanted surface of thefirst side surfaces maintains an angle of χ with respect to a normalperpendicular to the upper surface of the first flooring, and thesupplemental slanted surface of the second side surfaces maintains anangle of δ with respect to the normal, wherein χ and δ satisfy thefollowing conditions: χ=0˜8°, δ=0˜8°, χ≧δ, χ+δ=0˜16°
 9. The plasticflooring of claim 6, wherein the first side surface provides aperpendicular surface connected to the abutting surface of the concaveportion at the lower surface of the first flooring, and the second sidesurface provides a perpendicular surface connected to the abuttingsurface of the convex portion at the lower surface of the secondflooring so that a heat expansion tolerance portion is provided betweenthe perpendicular surfaces of the first and second side surfaces. 10.The plastic flooring of claim 9 wherein the gap d1 between theperpendicular surfaces formed on the first and the second side surfacesare identical to the gap d2 between the perpendicular surfaces formedbetween the concave portion and the convex portion.
 11. The plasticflooring of claim 9, wherein the gap d1 between the perpendicularsurfaces formed on the first and the second side surfaces is twice thegap d2 between the perpendicular surfaces formed on the concave portionand the convex portion.
 12. The plastic flooring of claim 4, wherein thethickness starting from the upper surface of the first and the secondfloorings to the slanted surfaces of the concave portion and the convexportion, the thickness of the slanted surfaces of the concave portionand the convex port ion, the thickness of the perpendicular surfaces ofthe convex portion and the concave portion, and the thickness startingfrom the abutting surfaces of the concave portion and the convex portionto the lower surface of the first and the second floorings are ¼ of thetotal thickness of the first and the second floorings.
 13. The plasticflooring of claim 1, wherein the concave portions are formed on twoadjacent sides of the plastic flooring and the convex portions areformed on the two remaining side surfaces.
 14. The plastic flooring ofclaim 1, wherein the plastic floorings comprise a first group offloorings in which the concave portions are formed on three adjacentside surfaces and the convex portions are formed on one remaining sidesurface, and a second group of floorings in which the convex portionsare formed on three adjacent side surfaces and the concave portions areformed on the remaining one side surface.
 15. The plastic flooring ofclaim 1, wherein the plastic floorings include a first group offloorings in which the concave portions are formed on all four sides ofthe plastic flooring and a second group of floorings in which the convexportions are formed on all four side surfaces of the plastic flooring.16. The plastic flooring of claim 1, wherein the first and the secondfloorings comprise, a substrate layer composed of plastic; a surfacelayer located at the upper surface of the substrate layer attributingpattern; and a balance layer located at the lower surface of thesubstrate layer attributing dimension stability.
 17. The plasticflooring of claim 16 wherein the surface layer and the balance layer arebeveled.